This relates to methods and apparatus in a cantilevered frame part of a press section and/or wire section of a paper machine in which a cantilevered beam attached between the side frames of the paper machine is pre-tensioned by applying a predetermined force in a downward direction of the projecting part of the cantilevered beam.
It is known in the prior art to provide cantilevered beams as part of the paper machine frame. The cantilevered beams extend in the transverse direction of the paper machine and are arranged in a manner such that at the service side of the paper machine, intermediate pieces situated between the beam and the frame are openable by means of power units. When opened, the intermediate pieces provide an opening through which closed fabric loops of the paper machine can be inserted and positioned around the rolls and cross beams in connection with the replacement of the fabrics. In a manner known in the prior art, the projecting parts of the cantilevered beams which are situated at the other side of the paper machine, i.e., the operation side of the paper machine opposite from the service side at which the openable intermediate pieces are situated, are fixed to the ceiling, wall or floor of the paper machine hall, and most commonly are fastened to projecting parts of the wall of the paper machine hall by means of massive threaded members. The threaded fastening members function to support the cantilevered beam when the intermediate pieces on the service side of the machine frame are opened.
The known manner of fastening the projecting part of the cantilevered beam involves certain drawbacks resulting from the fact that the fastening members are under tension at all times. For this reason, oscillations or vibrations spread from the paper machine frame through the fastening members to the wall construction of the paper machine hall which, among other things, significantly increases the noise level in the paper machine hall.
Another drawback of conventional tensioning fastening arrangements is that the large forces applied by them to the cantilevered beams may cause the long frame beams to deform. This can adversely affect, for example, the parallel alignment of the axles of the various paper machine rolls.